Expandable paddle distractor

ABSTRACT

Implementations described herein include surgical distraction devices having a distal movement assembly having a pusher plate comprising a first slot extending along a first axis disposed in a first side and a second slot extending along a second axis disposed in a second side thereof. The first axis is oriented at an angle of from about 60 to about 160 degrees from the second axis. The device further includes a first and second paddles, each paddle having a corresponding engagement mechanism for movably coupling the respective first or second paddle to the pusher plate when engaged in the respective slot. Rotational actuation of the proximal drive assembly causes proximal or distal movement of the pusher plate, causing the first and second engagement members to move relative to their respective slots, thereby moving the first paddle and the second paddle in opposing directions. Methods of using such surgical distraction devices to determine size of an intervertebral space are also described.

PRIORITY APPLICATION

This application claims the benefit of priority to U.S. ProvisionalApplication Ser. No. 62/289,399, filed Feb. 1, 2016, the content ofwhich is incorporated hereby by reference in its entirety.

FIELD

The present disclosure relates to expandable paddle distractors andassociated systems and methods.

BACKGROUND

Spinal surgeries that require implantation of devices intointervertebral spaces are well known. In order to determine anappropriate size intervertebral implant, it may be necessary to usetools to measure the intervertebral space. Currently used tools mayinclude tools that include snap-on heads of varying size that areswitched out until the appropriate diameter across the intervertebralspace is determined. Alternatively, a number of different tools, each ofdifferent size, may be used.

SUMMARY

The present inventors have recognized, among other things, that aproblem to be solved can include the need for use of multipledifferently-sized surgical distractors in order to make sizedeterminations of intervertebral spaces. The present subject matter canhelp provide a solution to this problem, such as by providing a singleexpandable surgical distractor.

The surgical distractor of the present description can comprise a distalmovement assembly comprising a pusher plate and a proximal driveassembly coupled to a proximal end of the pusher plate. The pusher platecan comprise a first slot disposed therein extending along a first axisand a second slot disposed therein extending along a second axis. Thefirst slot can extend from a first side of the pusher plate towards anopposed second side of the pusher plate and the second slot can extendfrom a second side of the pusher plate towards the first side. The firstaxis can oriented at an angle of between about 60 degrees and about 160degrees with respect to the second axis. The surgical distractor canfurther comprise a first paddle and a second paddle. The first paddlecan comprise a first actuation plate and a first engagement platesubstantially transverse to the first actuation plate. The first paddlecan further comprise a first engagement member coupled to the firstactuation plate for movably coupling the first paddle to the pusherplate when engaged with the first slot. The second paddle can comprise asecond actuation plate and a second engagement plate substantiallytransverse to the second actuation plate. The second paddle can furthercomprise a second engagement member coupled to the second actuationplate for movably coupling the second paddle to the pusher plate whenengaged with the second slot. Rotational activation of the proximaldrive assembly can cause proximal or distal movement of the pusherplate, causing the first engagement member to move relative to the firstslot and the second engagement member to move relative to the secondslot, thereby moving the first paddle and the second paddle in opposingdirections. Each of the opposing directions can be orthogonal to alongitudinal axis of the device.

The present description also provides for another method of determiningthe size of an intervertebral space. The method can comprise inserting adistal end of a distractor into an intervertebral space; attempting toturn the distal end of the distractor 90 degrees such that an axisthrough a greatest width of the distal end is aligned with the axis ofthe spine; engaging a proximal drive assembly of the distractor to movea pusher plate of the distractor along a longitudinal axis of thedistractor, wherein engagement members disposed on each of the first andsecond paddle of the distractor engage with slots disposed in the pusherplate to cause the paddles to translate away from a longitudinal axis ofthe proximal drive assembly; and determining an implant sizecorresponding to the width of the distractor in the plane in which thefirst and second paddles are translated using an implant size indicator.

The present description further provides for method of determining thesize of an intervertebral space. The method can comprise inserting adistal end of a distractor into an intervertebral space; attempting toturn the distal end of the distractor 90 degrees such that an axisthrough a greatest width of the distal end is aligned with the axis ofthe spine; returning the distractor to its original orientation;engaging a proximal drive assembly of the distractor to move a pusherplate of the distractor along a longitudinal axis of the distractor,wherein engagement members disposed on each of the first and secondpaddle of the distractor engage with slots disposed in the pusher plateto cause the paddles to translate away from a longitudinal axis of theproximal drive assembly; attempting, an additional time, to turn thedistal end of the distractor 90 degrees such that an axis through agreatest width of the distal end is aligned with the axis of the spine;and repeating the method until the maximum diameter of the distal end ofthe distractor that is capable of fitting snugly within theintervertebral space in an upright configuration is determined.

This overview is intended to provide an overview of subject matter ofthe present patent application. It is not intended to provide anexclusive or exhaustive explanation of the invention. The detaileddescription is included to provide further information about the presentpatent application.

DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. Like numerals havingdifferent letter suffixes may represent different instances of similarcomponents. The drawings illustrate generally, by way of example, butnot by way of limitation, various embodiments discussed in the presentdocument.

FIG. 1 provides a perspective view of an exemplary surgical distractiondevice according to the present description.

FIG. 2A provides a perspective view of internal components of anexemplary surgical distraction device according to the presentdescription.

FIG. 2B provides a perspective view of an exemplary pusher plateaccording to the present description.

FIG. 3A provides a perspective view of a distal end of one exemplarysurgical distraction device according to the present description.

FIG. 3B provides a close up view of one exemplary paddle according tothe present description.

FIG. 3C provides a cross sectional view corresponding to section line 3Cin FIG. 3A.

FIG. 4A provides an exploded perspective view of a distal end of oneexemplary surgical distraction device according to the presentdescription.

FIG. 4B provides an assembled perspective view of the distal end of thesurgical distractor of FIG. 4A according to the present description.

FIG. 5 provides a close up perspective view of an indicator on anexemplary surgical distraction device according to the presentdescription.

FIG. 6A provides a cross-sectional view of internal portions of anexemplary pusher plate according to the present description.

FIG. 6B provides perspective views of external portions of an exemplarypusher plate according to the present description.

FIG. 6C provides a perspective view of a threaded connector.

FIG. 6D provides a perspective view of portions of an exemplary surgicaldistraction device according to the present description.

FIG. 7A provides a cross-sectional view of portions of an exemplarysurgical distraction device according to the present description.

FIGS. 7B-7D provide close up cross-sectional views of the portions ofthe surgical distraction device of FIG. 7A.

FIG. 8 provides a perspective view of exemplary paddles in relation tothe housing surrounding said paddles.

FIG. 9 provides a side view of an exemplary turning nut according to thepresent description.

FIG. 10A provides a cross-sectional view an exemplary surgicaldistraction device according to the present description.

FIGS. 10B and 10C provide close up cross-sectional views of the surgicaldistraction device of FIG. 9A in two stages.

FIGS. 11A-11I provide various illustrations of an exemplary surgicaldistraction device and intervertebral space during one possible methodof use.

FIGS. 12A-12J provide various illustrations of an exemplary surgicaldistraction device and intervertebral space during one possible methodof use.

DETAILED DESCRIPTION

The present description relates to a surgical distraction device thatallows for more efficient sizing of intervertebral spaces. As notedabove, presently used devices for measuring intervertebral spaces sufferthe drawback of the requirement of removing the device from the spaceentirely in order to replace with a larger or smaller sized head, orsubstituting in an entirely different device. The present descriptionprovides for a device that can be expanded to varying sizes until theintervertebral space (and corresponding implant size determination) ismade, without removing the device entirely from the space.

FIG. 1 provides a perspective view of an exemplary surgical distractiondevice 100 according to the present description. In general, thesurgical distraction device can comprise a first paddle 114 and a secondpaddle 118 that are slidably coupled to a pusher plate 108 (shown inFIGS. 2A-2B) such that proximal and distal movement of the pusher platecauses the first and second paddles 114, 118 to move in opposingdirections that are substantially transverse to the longitudinal axis ofthe device 100. The pusher plate 108 can be rotationally actuated by aproximal drive assembly 110 that is coupled to a proximal end of thepusher plate 108 (shown in FIGS. 2A-2B). A turning nut 124 can becoupled to the proximal drive assembly 110 and manipulation of theturning nut 124 can actuate the proximal drive assembly 110. The device100 can further comprise an indicator 130 that displays the size of theintervertebral implant that corresponds to a given distance between anouter side 132 of the first paddle 114 and the outer side 132 of thesecond paddle 118. The device can also comprise a housing 140 that canbe configured to surround the proximal drive assembly 110. Thesefeatures will each be described more particularly in the followingdescription.

As further illustrated in FIGS. 2A-2B, the surgical distraction device100 can comprise a distal movement assembly 102 at the distal endthereof that is movably coupled to a first paddle 114 and a secondpaddle 118. Distal movement assembly 102 can comprise a pusher plate 108and a proximal drive assembly 110 coupled to a proximal end of thepusher plate 108. The pusher plate 108 can comprise a first slot 116disposed therein an extending along a first axis and a second slot 117disposed therein extending along a second axis. The first slot 116 canextend from a first side 104 of the pusher plate 108 towards a secondside 106 of the pusher plate 108 and the second slot 117 can extend froma second side 106 of the pusher plate 108 towards the first side 104.The first and second slots 116, 117 can extend partially through orcompletely through the pusher plate 108. In at least one example, thepusher plate 108 can comprise a threaded coupling portion 128 (see,e.g., FIG. 2B) near distal end 112 that can be mateable with internalthreads of the proximal drive assembly 110 in order to secure theproximal drive assembly 110 to the pusher plate 108.

As further illustrated in FIGS. 3A-4B, the distraction device 100 canfurther comprise a first paddle 114 and a second paddle 118. The firstpaddle 114 and the second paddle 118 can each comprise, respectively, afirst engagement member 120 and a second engagement member 122. Thedistal movement assembly 102 can be actuated to move the first paddle114 and the second paddle 118 towards or away from each other asdescribed in further detail below.

In one example illustrated in FIGS. 3A-3C, the surgical distractiondevice 100 can comprise a first paddle 114 and a second paddle 118. Thefirst paddle 114 can comprise a first actuation plate 121 and a firstengagement plate 123 that can be substantially transverse to the firstactuation plate 121. The first paddle 114 can further comprise a firstengagement member 120 coupled to and extending from the first actuationplate 121 for movably coupling the first paddle 114 to the pusher plate108. Likewise, the second paddle 118 can comprise a second actuationplate 125 and a second engagement plate 127 that can be substantiallytransverse to the first actuation plate 125. The second paddle 118 canfurther comprise a second engagement member 122 coupled to and extendingfrom the second actuation plate 125 for movably coupling the secondpaddle 118 to the pusher plate 108. Accordingly, the paddles 114, 118engage the pusher plate 108 via engagement members (such as 120, 122)disposed on actuation plates (such as 121, 125) sliding within slots(such as 116, 117). The first engagement member 120 can comprise a firstrail for engaging the first slot 116 on the first side 104 of the pusherplate 108 and the second engagement member 122 can comprise a secondrail for engaging the second slot 117 on the second side 106 of thepusher plate 108. The first engagement member 120 and the first slot 116and the second engagement member 122 and the second slot 117 can bematingly keyed as best illustrated in FIG. 3C. The first slot 116 of thepusher plate 108 can comprise a plurality of first slots 116 and thefirst engagement member 120 can comprise a corresponding plurality offirst engagement members 120. Likewise, the second slot 117 of thepusher plate 108 can comprise a plurality of second slots 117 and thesecond engagement member 122 can comprise a corresponding plurality ofsecond engagement members 122.

In another example illustrated in FIGS. 4A-4B, the surgical distractiondevice 400 can comprise a first paddle 414 and a second paddle 418. Thefirst paddle 414 can comprise a first actuation plate 421 and a firstengagement plate 423 that can be substantially transverse to the firstactuation plate 421. The first paddle 414 can further comprise a firstengagement member 420 coupled to the first actuation plate 421 formovably coupling the first paddle 414 to the pusher plate 408. Likewise,the second paddle 418 can comprise a second actuation plate 425 and asecond engagement plate 427 that can be substantially transverse to thefirst actuation plate 425. The second paddle 418 can further comprise asecond engagement member 422 coupled to the second actuation plate 425for movably coupling the second paddle 418 to the pusher plate 408.Accordingly, as with the example described above, the paddles 414, 418engage the pusher plate 408 via engagement members (such as 420, 422)disposed on actuation plates (such as 421, 425) sliding within slots(such as 416, 417). The first engagement member 420 can comprise a firstpin coupled to and extending from the first actuation plate 421 forengaging the first slot 416 of the pusher plate 408 and the secondengagement member 422 can comprise a second pin coupled to and extendingfrom the second actuation plate 425 for engaging the second slot 417 onthe second side 406 of the pusher plate 408. The first slot 416 of thepusher plate 408 can comprise a plurality of first slots 416 and thefirst engagement member 420 can comprise a corresponding plurality offirst engagement members 420. Likewise, the second slot 417 of thepusher plate 408 can comprise a plurality of second slots 417 and thesecond engagement member 422 can comprise a corresponding plurality ofsecond engagement members 422. In another example, the surgicaldistraction device can further comprise a support member 429 having afirst support 431 and a second support 432 spaced from the firstsupport. The support member 429 can be positioned such that the firstactuation plate 423 is substantially parallel to and in between thefirst support 431 and the pusher plate 408 and that the second actuationplate 427 is substantially parallel to and in between the second support433 and the pusher plate 408. The first and second supports 431, 433 canhave slots 435, 437 disposed therein that correspond to at least one ofthe first and second slots (or plurality of slots) 416, 417 disposed inthe pusher plate 408. The support member 429 can provide further supportfor the first and second paddles 414, 418 as they translate or can beconfigured to facilitate relative movement between the first and secondpaddles 414, 418.

In each of the examples described above, the first and second engagementplates (such as 123, 127, 423, 427) can provide surface area to abutanatomical structure during use of the distraction device (such as 100,400). Additionally, the edges of the first and second engagement plates(such as 123, 127, 423, 427) that abut the first and second actuationplates (such as 121, 125, 421, 425) can optionally be chamfered orrounded (not specifically identified in the illustrations) to smoothtransitions between the various surfaces and ease the ability tomanipulate the surgical distraction device (such as 100, 400) duringuse.

In each of the examples described above, rotational actuation of theproximal drive assembly (such as 110, 410) causes proximal or distalmovement of the pusher plate (such as 108, 408) engaging the first andsecond engagement members (such as 120, 122, 420, 422). Proximal/distalmovement of the proximal drive assembly (such as 110, 410) can move thefirst and second engagement members (such as 120, 122, 420, 422) withinthe corresponding slots (such as 116, 117, 416, 417), thereby moving thefirst paddle (such as 114, 414) and the second paddle (such as 118, 418)in opposing directions (D1 and D2). The opposing directions can beorthogonal to longitudinal axis A₁ of the surgical distraction deviceand proximal drive assembly. The rotation of the proximal drive assembly(such as 110, 410) can occur within (and is generally hidden by) turningnut 124, which surrounds at least a portion of the proximal driveassembly.

In each of the examples described above, the plurality of first slots(such as 116, 416) on the first slotted surface (such as 104, 404) canbe positioned parallel to one another and the plurality of second slots(such as 117, 417) on the second slotted surface (such as 106, 406) canbe positioned parallel to one another. The first slots (such as 116,416) on the first slotted surface (such as 104, 404) can be generallyoriented with respect to the second slots (such as 117, 417) on thesecond slotted surface (such as 106, 406) at an angle θs. In someexamples, θs can be an angle between about 60 degrees and about 160degrees, more particularly, θs can be a value between about 75 degreesand about 105 degrees, and, most particularly, θs can be a value between80 degrees and 100 degrees.

Returning to FIG. 1, in at least one example, the surgical distractiondevice can comprise a turning nut 124 that is coupled to the proximaldrive assembly 110. In such an example, manipulating the turning nut 124can result in advancing or retracting of the pusher plate 108, and thusmovement of the first and second paddles 114 and 118. For example, inthe illustrated exemplary embodiment of FIGS. 3A-3C, retracting thepusher plate 108 with the distal movement assembly 102 can cause thefirst paddle 114 and second paddle 118 to expand outward from the pusherplate 108 and advancing the pusher plate 108 can cause the first paddle114 and second paddle 118 to contract toward the pusher plate 108. Theturning nut 124 may be threadably engaged with the proximal driveassembly 110 and the proximal end of the surgical distraction device100, e.g., at threaded engagement portion 126 (see FIG. 2A).

As further illustrated in FIG. 5, the surgical distraction devices 100of the present description can further comprise an indicator 130 thatdisplays the size of intervertebral implant that corresponds to a givendistance from an outer side 132 of the first paddle 114 to an outer side132 of the second paddle 118. The indicator 130 can be positionedproximate the turning nut 124. The indicator 130 may comprise anindicator pin 148 that translates along a slot 152 as the paddles 114,118 expand and contract. In an example, the indicator pin 148 is coupledto a portion of the proximal drive assembly 110, which translatesrelative to housing 140. The indicator pin 148 can display theintervertebral implant size according to size markings 154 positionedalong the edge of the slot 152 that correspond to the distance from anouter surface of the first engagement plate 123 to the outer surface ofthe second engagement plate 127. In one example, the size markings 154are calibrated to reflect the distraction distance based on thetranslation of the indicator 130 caused by movement of the proximaldrive assembly 110.

FIG. 6A illustrates a cross-sectional view of a number of the componentsof the surgical distraction device, including the pusher plate 108,proximal drive assembly 110, and turning nut 124. As illustrated in FIG.6B, the surgical distraction devices 100 can further comprise a housing140. The housing 140 can be configured to surround the proximal driveassembly 110 (though shown separately in FIG. 6B). The fully assembleddistraction device 100 with housing surrounding proximal drive assembly110 is shown in FIG. 1. The housing 140 can surround the proximal driveassembly 110 and also partially surround the pusher plate 108, the firstpaddle 114, and the second paddle 118. The turning nut 124 can also atleast partially surround the proximal drive assembly 110. The turningnut 124 can be coupled to the proximal drive assembly 110 via a threadedquick connect device 150, shown in FIG. 6C. As illustrated in FIG. 6D,the threaded quick connect device 150 can be mechanically coupled to theproximal drive assembly 110. The threaded quick connect device 150 cancomprise external threads 152 that can be capable of engaging internalthreads of the turning nut 124 at a rear portion of the turning nut 154(see FIG. 6A) thus enabling manipulation of the turning nut 124 toactuate the proximal drive assembly 110.

This concept can be further understood by references to FIGS. 7A to 7D.FIGS. 7A and 7B provides cross-sectional views of a surgical distractiondevice 100 shown without turning nut 124 present. The proximal driveassembly 110, pusher plate 108, and quick connect device 150 cancooperatively form the distal movement assembly 102. The housing 140 canbe coupled to the distal movement assembly 102 via the indicator pin 148(shown in FIGS. 7C and 7D). This can prevent rotation of the housing 140relative to the distal movement assembly 102 but can allow for somemovement along the longitudinal axis A₁ (illustrated in FIG. 3A) of theproximal drive assembly 110. Translation of the housing 140 relative tothe proximal drive assembly 110 causes the two paddles 114, 118 todistract/contract.

The turning nut 124 can facilitate translation of the housing 140relative to the proximal drive assembly 110. The turning nut 124 can becoupled to the housing 140 via two pins 156, as shown in FIG. 9. Thesepins 156 can couple the turning nut 124 and the housing 140 in thelongitudinal axis but still allow for the nut 124 to be rotated relativeto the housing 140. When a user grasps to the turning handle 144 andbegins rotating the turning nut 124, the turning nut 124 travels alongthe longitudinal axis A₁ of the proximal drive assembly and pushes/pullsthe housing 140 along with it, thus expanding/contracting the paddles114, 118 without rotating the housing 140. FIG. 10A shows across-sectional view of the surgical distraction device 100, and FIGS.10B and 10C provide close-up cross-sectional views of the turning nut124 at two different positions along the longitudinal axis A₁ of theproximal drive assembly 110. Alternatively, if a user holds on to theturning nut 124 and begins rotating the turning handle 144, the distalend of the surgical distraction device does rotate while simultaneouslyexpanding/contracting the paddles 114,118.

The surgical distraction devices 100 described herein can be used todetermine the distance between adjacent vertebrae. For example, thesurgical distraction device 100 can be inserted between two vertebrae ofa patient, among other surgical uses. In one example, the surgicaldistraction device 100 can be rotated after insertion into theintervertebral space (i.e. the space between the two adjacent vertebrae)in order to facilitate determination of the distance across theintervertebral space, as further described below.

FIGS. 11A-11 l illustrate one method of determining a space between twoadjacent vertebrae according to one example. As shown in FIGS. 11A and11B, the method can comprise inserting a distal end 142 of a distractor100 into an intervertebral space 650. The distractor 100 of the methodsdescribed herein can generally relate to the distracters described inthe previous figures, and thus any element numbers not specificallyshown in the figures reference those provided in the foregoing figures.Next, the method can comprise attempting to rotate the distal end 142 ofthe distractor 100 to approximately ninety degrees such that an axisthough a greatest width of the distal end (A₂) is aligned with the axisof the spine (A₃) (see FIG. 11E). As shown in FIG. 11D, the sizeindicator 130 may be in a first position P₁ that illustrates the size ofimplant that corresponds to the width across the paddles 114, 118, whereat size P₁ the paddles have not been expanded outward from the pusherplate 108. The distal end 142 of the distractor 100 can be manipulatedby the turning handle 144 at the proximal end 146 of distractor 100which is coupled to the quick connect device 150. As shown in FIG. 11F,next the distractor 100 can be returned to its original orientation,likely where the paddle is in a substantially horizontal position withinthe intervertebral space 650. Additionally, the proximal drive assembly110 can be actuated such that the first and second paddles 114, 118translate away from a longitudinal axis A₃ of the proximal driveassembly 110 by engaging the turning nut 124 in place and rotating theturning handle 144. Next, as shown in FIGS. 11G, 11H and 11I, afterexpanding the paddles a certain distance, the operator can attempt, asecond time, to turn the distal end 142 of distractor 100 ninety degreessuch that axis A₂ is aligned with spinal axis A₃. Once again, theindicator 130 may be read to indicate the size of intervertebral implantthat corresponds to a current distance across the width of thedistractor, here shown by position P₂ on the indicator. This process canbe repeated until the maximum diameter of the distal end 142 of thedistractor 100 is capable of fitting snugly within the intervertebralspace 650 when in an upright configuration (i.e. where the greatestwidth of the distractor aligned with the longitudinal axis of thespine). In the case where the distal end 142 of the distractor 100 isturned but incapable of fully rotating to 90 degrees to alignment withthe spinal axis A₃, the surgeon will understand that the implant sizecorresponding to the most previous attempt to rotate the distractor willbe the largest implant that can suitably fit in the intervertebralspace.

Another exemplary method of use is provided in FIGS. 12A-12G. The methodcan comprise inserting a distal end 142 of a distractor 100 into anintervertebral space 650, as shown in FIGS. 12A and 12B. Next, theoperator can attempt to rotate the distal end 142 of the distractor 100ninety degrees such that an axis through a greatest width of the distalend A₂ is aligned with the axis of the spine A₃ (as illustrated in FIGS.12C, 12D and 12E), potentially using handle 144. The operator can thenengage a proximal drive assembly 110 of the distractor 100 to cause thepaddles to expand from a longitudinal axis of the proximal driveassembly 110 until the first and second engagement plates 123, 127 ofthe first and second paddles 114, 118 contact the first and secondvertebrae bounding the intervertebral space. The mechanism of expandingthe paddles is shown in FIG. 12F. Once the paddles 114 and 118 haveencountered resistance against the surfaces of the adjacent vertebrae,the width of the distractor 100 can be determined using the sizeindicator 130. FIGS. 12G and 12H, and 12I and 12J, show the indicator atvarying sizes including at position P2, which equates to an 8 mmimplant, and position P3, which equates to a 9 mm implant. The width ofthe distractor in the plane in which the first and second paddles aretranslated after the paddles contact the first and second vertebra isequivalent to the distance across the intervertebral space.

In either method of use, the size determination of the intervertebralspace can be used to choose an appropriately sized intervertebralimplant, which can subsequently be implanted into the intervertebralspace.

VARIOUS NOTES & EXAMPLES

Example 1 is a device comprising: a distal movement assembly comprisinga pusher plate and a proximal drive assembly coupled to a proximal endof the pusher plate, the pusher plate comprising a first slot disposedtherein extending along a first axis and a second slot disposed thereinextending along a second axis, wherein the first slot extends from afirst side of the pusher plate towards an opposed second side of thepusher plate, wherein the second slot extends from a second side of thepusher plate towards the first side, wherein the first axis is orientedat an angle of between about 60 degrees and about 160 degrees withrespect to the second axis; a first paddle comprising a first actuationplate and a first engagement plate substantially transverse to the firstactuation plate, the first paddle further comprising a first engagementmember coupled to the first actuation plate for movably coupling thefirst paddle to the pusher plate when engaged with the first slot; and asecond paddle comprising a second actuation plate and a secondengagement plate substantially transverse to the second actuation plate,the second paddle further comprising a second engagement member coupledto the second actuation plate for movably coupling the second paddle tothe pusher plate when engaged with the second slot; wherein rotationalactivation of the proximal drive assembly causes proximal or distalmovement of the pusher plate, causing the first engagement member tomove relative to the first slot and the second engagement member to moverelative to the second slot, thereby moving the first paddle and thesecond paddle in opposing directions, each of the opposing directionsorthogonal to a longitudinal axis of the device.

In Example 2, the subject matter of Example 1 optionally includeswherein the first engagement member comprises a first pin coupled to andextending from the first actuation plate.

In Example 3, the subject matter of Example 2 optionally includeswherein the second engagement member comprises a second pin coupled toand extending from the second actuation plate.

In Example 4, the subject matter of Example 3 optionally includes ahousing that fully surrounds the proximal drive assembly and partiallysurrounds the pusher plate and first and second paddles.

In Example 5, the subject matter of Example 4 optionally includeswherein a first interior side of the housing has a first housing slotdisposed therein that extends toward to the first exterior side of thehousing that extends along the first axis of the first slot of thepusher plate, wherein a second interior side of the housing has a secondhousing slot disposed therein that extends toward to the second exteriorside of the housing that extends along the second axis of the secondslot of the pusher plate, wherein the first pin is movably coupleable tothe first housing slot and the second pin is movable coupleable to thesecond housing slot.

In Example 6, the subject matter of any one or more of Examples 1-5optionally include wherein the first engagement member comprises a firstrail extending along at least a portion of the first actuation platealong the first axis of the first slot of the pusher plate, wherein thefirst rail and the first slot are matingly keyed.

In Example 7, the subject matter of Example 6 optionally includeswherein the second engagement member comprises a second rail extendingalong at least a portion of the second actuation plate along the secondaxis of the second slot of the pusher plate, wherein the second rail andthe second slot are matingly keyed.

In Example 8, the subject matter of Example 7 optionally includes ahousing that fully surrounds the proximal drive assembly and partiallysurrounds the pusher plate and first and second paddles.

In Example 9, the subject matter of any one or more of Examples 1-8optionally include wherein the first slot comprises a first plurality ofslots and wherein the first engagement member comprises a correspondingplurality of first engagement members.

In Example 10, the subject matter of Example 9 optionally includeswherein the second slot comprises a second plurality of slots andwherein the second engagement member comprises a corresponding pluralityof second engagement members.

In Example 11, the subject matter of Example 10 optionally includeswherein first plurality of slots are parallel to one another and whereinthe second plurality of slots are parallel to one another.

In Example 12, the subject matter of any one or more of Examples 1-11optionally include wherein the pusher plate is threadably coupleable tothe proximal drive assembly.

In Example 13, the subject matter of Example 12 optionally includes aturning nut coupled to the proximal drive assembly, wherein turning ofthe turning nut results in proximal or distal movement of the pusherplate.

In Example 14, the subject matter of Example 13 optionally includeswherein the turning nut is threadably engageable with the proximal driveassembly.

In Example 15, the subject matter of any one or more of Examples 1-14optionally include an indicator that displays an implant sizecorresponding to the distance from an outer surface of the firstengagement plate to an outer surface of the second engagement plate.

In Example 16, the subject matter of any one or more of Examples 1-15optionally include wherein a distal end of the device insertable betweenadjacent vertebrae.

In Example 17, the subject matter of Example 16 optionally includeswherein the device is actuable to determine the distance betweenadjacent vertebrae.

Example 18 is a device, comprising: a distal movement assemblycomprising a pusher plate and a proximal drive assembly coupled to aproximal end of the pusher plate, the pusher plate comprising a firstslot disposed therein extending along a first axis and a second slotdisposed therein extending along a second axis, wherein the first slotextends from a first side of the pusher plate towards an opposed secondside of the pusher plate, wherein the second slot extends from a secondside of the pusher plate towards the first side, wherein the first axisis oriented at an angle of between about 60 degrees and about 160degrees with respect to the second axis; a first paddle comprising afirst actuation plate and a first engagement plate substantiallytransverse to the first actuation plate, the first paddle furthercomprising a first pin coupled to and extending from the first actuationplate for movably coupling the first paddle to the pusher plate whenengaged with the first slot; and a second paddle comprising a secondactuation plate and a second engagement plate substantially transverseto the second actuation plate, the second paddle further comprising asecond pin coupled to and extending from the second actuation plate formovably coupling the second paddle to the pusher plate when engaged withthe second slot; wherein rotational activation of the proximal driveassembly causes proximal or distal movement of the pusher plate, causingthe first engagement member to move relative to the first slot and thesecond engagement member to move relative to the second slot, therebymoving the first paddle and the second paddle in opposing directions,each of the opposing directions orthogonal to a longitudinal axis of thedevice.

In Example 19, the subject matter of Example 18 optionally includes ahousing that fully surrounds the proximal drive assembly and partiallysurrounds the pusher plate and first and second paddles, wherein a firstinterior side of the housing has a first housing slot disposed thereinthat extends toward to the first exterior side of the housing thatextends along the first axis of the first slot of the pusher plate,wherein a second interior side of the housing has a second housing slotdisposed therein that extends toward to the second exterior side of thehousing that extends along the second axis of the second slot of thepusher plate, wherein the first pin is movably coupleable to the firsthousing slot and the second pin is movable coupleable to the secondhousing slot.

Example 20 is a device, comprising: a distal movement assemblycomprising a pusher plate and a proximal drive assembly coupled to aproximal end of the pusher plate, the pusher plate comprising a firstslot disposed therein extending along a first axis and a second slotdisposed therein extending along a second axis, wherein the first slotextends from a first side of the pusher plate towards an opposed secondside of the pusher plate, wherein the second slot extends from a secondside of the pusher plate towards the first side, wherein the first axisis oriented at an angle of between about 60 degrees and about 60 degreeswith respect to the second axis; a first paddle comprising a firstactuation plate and a first engagement plate substantially transverse tothe first actuation plate, the first paddle further comprising a firstrail coupled to and extending along at least a portion of the firstactuation plate along the first axis of the first slot of the pusherplate for movably coupling the first paddle to the pusher plate whenengaged with the first slot; and a second paddle comprising a secondactuation plate and a second engagement plate substantially transverseto the second actuation plate, the second paddle further comprising asecond rail coupled to and extending along at least a portion of thesecond actuation plate along the second axis of the second slot of thepusher plate for movably coupling the second paddle to the pusher platewhen engaged with the second slot; wherein rotational activation of theproximal drive assembly causes proximal or distal movement of the pusherplate, causing the first engagement member to move relative to the firstslot and the second engagement member to move relative to the secondslot, thereby moving the first paddle and the second paddle in opposingdirections, each of the opposing directions orthogonal to a longitudinalaxis of the device.

In Example 21, the subject matter of Example 20 optionally includeswherein the first rail and the first slot are matingly keyed and whereinthe second rail and the second slot are matingly keyed.

Example 22 is a method of determining the size of an intervertebralspace, comprising: inserting a distal end of a distractor into anintervertebral space; attempting to turn the distal end of thedistractor 90 degrees such that an axis through a greatest width of thedistal end is aligned with the axis of the spine; engaging a proximaldrive assembly of the distractor to move a pusher plate of thedistractor along a longitudinal axis of the distractor, whereinengagement members disposed on each of the first and second paddle ofthe distractor engage with slots disposed in the pusher plate to causethe paddles to translate away from a longitudinal axis of the proximaldrive assembly; determining an implant size corresponding to the widthof the distractor in the plane in which the first and second paddles aretranslated using an implant size indicator.

In Example 23, the subject matter of Example 22 optionally includeswherein the width of the distractor in the plane in which the first andsecond paddles are translated after the paddles contact the first andsecond vertebra is equivalent to the distance across the intervertebralspace.

Example 24 is a method of determining the size of an intervertebralspace, comprising: inserting a distal end of a distractor into anintervertebral space; attempting to turn the distal end of thedistractor 90 degrees such that an axis through a greatest width of thedistal end is aligned with the axis of the spine; returning thedistractor to its original orientation; engaging a proximal driveassembly of the distractor to move a pusher plate of the distractoralong a longitudinal axis of the distractor, wherein engagement membersdisposed on each of the first and second paddle of the distractor engagewith slots disposed in the pusher plate to cause the paddles totranslate away from a longitudinal axis of the proximal drive assembly;attempting, an additional time, to turn the distal end of the distractor90 degrees such that an axis through a greatest width of the distal endis aligned with the axis of the spine; and repeating the method untilthe maximum diameter of the distal end of the distractor that is capableof fitting snugly within the intervertebral space in an uprightconfiguration is determined.

In Example 25, the subject matter of Example 24 optionally includesretracting the first and second paddles in the event that the distractorcannot be rotated 90 degrees into an upright configuration by advancingthe proximal drive assembly in the distal direction.

In Example 26, the subject matter of any one or more of Examples 24-25optionally include determining an appropriately sized implant thatcorresponds to the width of the distractor in a plane in which the firstand second paddles are translating using an implant size indicator.

Each of these non-limiting examples can stand on its own, or can becombined in various permutations or combinations with one or more of theother examples.

The above detailed description includes references to the accompanyingdrawings, which form a part of the detailed description. The drawingsshow, by way of illustration, specific embodiments in which theinvention can be practiced. These embodiments are also referred toherein as “examples.” Such examples can include elements in addition tothose shown or described. However, the present inventors alsocontemplate examples in which only those elements shown or described areprovided. Moreover, the present inventors also contemplate examplesusing any combination or permutation of those elements shown ordescribed (or one or more aspects thereof), either with respect to aparticular example (or one or more aspects thereof), or with respect toother examples (or one or more aspects thereof) shown or describedherein.

In the event of inconsistent usages between this document and anydocuments so incorporated by reference, the usage in this documentcontrols.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more.” In thisdocument, the term “or” is used to refer to a nonexclusive or, such that“A or B” includes “A but not B,” “B but not A,” and “A and B,” unlessotherwise indicated. In this document, the terms “including” and “inwhich” are used as the plain-English equivalents of the respective terms“comprising” and “wherein.” Also, in the following claims, the terms“including” and “comprising” are open-ended, that is, a system, device,article, composition, formulation, or process that includes elements inaddition to those listed after such a term in a claim are still deemedto fall within the scope of that claim. Moreover, in the followingclaims, the terms “first,” “second,” and “third,” etc. are used merelyas labels, and are not intended to impose numerical requirements ontheir objects.

The above description is intended to be illustrative, and notrestrictive. For example, the above-described examples (or one or moreaspects thereof) may be used in combination with each other. Otherembodiments can be used, such as by one of ordinary skill in the artupon reviewing the above description. The Abstract is provided to complywith 37 C.F.R. §1.72(b), to allow the reader to quickly ascertain thenature of the technical disclosure. It is submitted with theunderstanding that it will not be used to interpret or limit the scopeor meaning of the claims. Also, in the above Detailed Description,various features may be grouped together to streamline the disclosure.This should not be interpreted as intending that an unclaimed disclosedfeature is essential to any claim. Rather, inventive subject matter maylie in less than all features of a particular disclosed embodiment.Thus, the following claims are hereby incorporated into the DetailedDescription as examples or embodiments, with each claim standing on itsown as a separate embodiment, and it is contemplated that suchembodiments can be combined with each other in various combinations orpermutations. The scope of the invention should be determined withreference to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

What is claimed is:
 1. A device, comprising: a distal movement assemblycomprising a pusher plate and a proximal drive assembly coupled to aproximal end of the pusher plate, the pusher plate comprising a firstslot disposed therein extending along a first axis and a second slotdisposed therein extending along a second axis, wherein the first slotextends from a first side of the pusher plate towards an opposed secondside of the pusher plate, wherein the second slot extends from a secondside of the pusher plate towards the first side, wherein the first axisis oriented at an angle of between about 60 degrees and about 160degrees with respect to the second axis; a first paddle comprising afirst actuation plate, a first engagement plate substantially transverseto the first actuation plate, and a first engagement member coupled tothe first actuation plate for movably coupling the first paddle to thepusher plate when engaged with the first slot; and a second paddlecomprising a second actuation plate and a second engagement platesubstantially transverse to the second actuation plate, the secondpaddle further comprising a second engagement member coupled to thesecond actuation plate for movably coupling the second paddle to thepusher plate when engaged with the second slot; wherein rotationalactivation of the proximal drive assembly causes proximal or distalmovement of the pusher plate, causing the first engagement member tomove relative to the first slot and the second engagement member to moverelative to the second slot, thereby moving the first paddle and thesecond paddle in opposing directions, each of the opposing directionsorthogonal to a longitudinal axis of the device.
 2. The device of claim1, wherein the first engagement member comprises a first pin coupled toand extending from the first actuation plate.
 3. The device of claim 2,wherein the second engagement member comprises a second pin coupled toand extending from the second actuation plate.
 4. The device of claim 3,further comprising a housing that fully surrounds the proximal driveassembly and partially surrounds the pusher plate and first and secondpaddles.
 5. The device of claim 4, wherein a first interior side of thehousing has a first housing slot disposed therein that extends toward tothe first exterior side of the housing that extends along the first axisof the first slot of the pusher plate, wherein a second interior side ofthe housing has a second housing slot disposed therein that extendstoward to the second exterior side of the housing that extends along thesecond axis of the second slot of the pusher plate, wherein the firstpin is movably coupleable to the first housing slot and the second pinis movable coupleable to the second housing slot.
 6. The device of claim1, wherein the first engagement member comprises a first rail extendingalong at least a portion of the first actuation plate along the firstaxis of the first slot of the pusher plate, wherein the first rail andthe first slot are matingly keyed.
 7. The device of claim 6, wherein thesecond engagement member comprises a second rail extending along atleast a portion of the second actuation plate along the second axis ofthe second slot of the pusher plate, wherein the second rail and thesecond slot are matingly keyed.
 8. The device of claim 7, furthercomprising a housing that fully surrounds the proximal drive assemblyand partially surrounds the pusher plate and first and second paddles.9. The device of claim 1, wherein the first slot comprises a firstplurality of slots and wherein the first engagement member comprises acorresponding plurality of first engagement members.
 10. The device ofclaim 9, wherein the second slot comprises a second plurality of slotsand wherein the second engagement member comprises a correspondingplurality of second engagement members.
 11. The device of claim 10,wherein first plurality of slots are parallel to one another and whereinthe second plurality of slots are parallel to one another.
 12. Thedevice of claim 1, wherein the pusher plate is threadably coupleable tothe proximal drive assembly.
 13. The device of claim 12, furthercomprising a turning nut coupled to the proximal drive assembly, whereinturning of the turning nut results in proximal or distal movement of thepusher plate.
 14. The device of claim 13, wherein the turning nut isthreadably engageable with the proximal drive assembly.
 15. The deviceof claim 1, further comprising an indicator that displays an implantsize corresponding to the distance from an outer surface of the firstengagement plate to an outer surface of the second engagement plate. 16.The device of claim 1, wherein a distal end of the device insertablebetween adjacent vertebrae.
 17. The device of claim 16, wherein thedevice is actuable to determine the distance between adjacent vertebrae.18. A device, comprising: a distal movement assembly comprising a pusherplate and a proximal drive assembly coupled to a proximal end of thepusher plate, the pusher plate comprising a first slot disposed thereinextending along a first axis and a second slot disposed thereinextending along a second axis, wherein the first slot extends from afirst side of the pusher plate towards an opposed second side of thepusher plate, wherein the second slot extends from a second side of thepusher plate towards the first side, wherein the first axis is orientedat an angle of between about 60 degrees and about 160 degrees withrespect to the second axis; a first paddle comprising a first actuationplate and a first engagement plate substantially transverse to the firstactuation plate, the first paddle further comprising a first pin coupledto and extending from the first actuation plate for movably coupling thefirst paddle to the pusher plate when engaged with the first slot; and asecond paddle comprising a second actuation plate and a secondengagement plate substantially transverse to the second actuation plate,the second paddle further comprising a second pin coupled to andextending from the second actuation plate for movably coupling thesecond paddle to the pusher plate when engaged with the second slot;wherein rotational activation of the proximal drive assembly causesproximal or distal movement of the pusher plate, causing the firstengagement member to move relative to the first slot and the secondengagement member to move relative to the second slot, thereby movingthe first paddle and the second paddle in opposing directions, each ofthe opposing directions orthogonal to a longitudinal axis of the device.19. The device of claim 18, further comprising a housing that fullysurrounds the proximal drive assembly and partially surrounds the pusherplate and first and second paddles, wherein a first interior side of thehousing has a first housing slot disposed therein that extends toward tothe first exterior side of the housing that extends along the first axisof the first slot of the pusher plate, wherein a second interior side ofthe housing has a second housing slot disposed therein that extendstoward to the second exterior side of the housing that extends along thesecond axis of the second slot of the pusher plate, wherein the firstpin is movably coupleable to the first housing slot and the second pinis movable coupleable to the second housing slot.
 20. A device,comprising: a distal movement assembly comprising a pusher plate and aproximal drive assembly coupled to a proximal end of the pusher plate,the pusher plate comprising a first slot disposed therein extendingalong a first axis and a second slot disposed therein extending along asecond axis, wherein the first slot extends from a first side of thepusher plate towards an opposed second side of the pusher plate, whereinthe second slot extends from a second side of the pusher plate towardsthe first side, wherein the first axis is oriented at an angle ofbetween about 60 degrees and about 160 degrees with respect to thesecond axis; a first paddle comprising a first actuation plate and afirst engagement plate substantially transverse to the first actuationplate, the first paddle further comprising a first rail coupled to andextending along at least a portion of the first actuation plate alongthe first axis of the first slot of the pusher plate for movablycoupling the first paddle to the pusher plate when engaged with thefirst slot; and a second paddle comprising a second actuation plate anda second engagement plate substantially transverse to the secondactuation plate, the second paddle further comprising a second railcoupled to and extending along at least a portion of the secondactuation plate along the second axis of the second slot of the pusherplate for movably coupling the second paddle to the pusher plate whenengaged with the second slot; wherein rotational activation of theproximal drive assembly causes proximal or distal movement of the pusherplate, causing the first engagement member to move relative to the firstslot and the second engagement member to move relative to the secondslot, thereby moving the first paddle and the second paddle in opposingdirections, each of the opposing directions orthogonal to a longitudinalaxis of the device.
 21. The device of claim 20, wherein the first railand the first slot are matingly keyed and wherein the second rail andthe second slot are matingly keyed.
 22. A method of determining the sizeof an intervertebral space, comprising: inserting a distal end of adistractor into an intervertebral space; attempting to turn the distalend of the distractor 90 degrees such that an axis through a greatestwidth of the distal end is aligned with the axis of the spine; engaginga proximal drive assembly of the distractor to move a pusher plate ofthe distractor along a longitudinal axis of the distractor, whereinengagement members disposed on each of the first and second paddle ofthe distractor engage with slots disposed in the pusher plate to causethe paddles to translate away from a longitudinal axis of the proximaldrive assembly; determining an implant size corresponding to the widthof the distractor in the plane in which the first and second paddles aretranslated using an implant size indicator.
 23. The method of claim 22,wherein the width of the distractor in the plane in which the first andsecond paddles are translated after the paddles contact the first andsecond vertebra is equivalent to the distance across the intervertebralspace.
 24. A method of determining the size of an intervertebral space,comprising: inserting a distal end of a distractor into anintervertebral space; attempting to turn the distal end of thedistractor 90 degrees such that an axis through a greatest width of thedistal end is aligned with the axis of the spine; returning thedistractor to its original orientation; engaging a proximal driveassembly of the distractor to move a pusher plate of the distractoralong a longitudinal axis of the distractor, wherein engagement membersdisposed on each of the first and second paddle of the distractor engagewith slots disposed in the pusher plate to cause the paddles totranslate away from a longitudinal axis of the proximal drive assembly;attempting, an additional time, to turn the distal end of the distractor90 degrees such that an axis through a greatest width of the distal endis aligned with the axis of the spine; and repeating the method untilthe maximum diameter of the distal end of the distractor that is capableof fitting snugly within the intervertebral space in an uprightconfiguration is determined.
 25. The method of claim 24, furthercomprising retracting the first and second paddles in the event that thedistractor cannot be rotated 90 degrees into an upright configuration byadvancing the proximal drive assembly in the distal direction.
 26. Themethod of claim 24, further comprising determining an appropriatelysized implant that corresponds to the width of the distractor in a planein which the first and second paddles are translating using an implantsize indicator.